Chap02

M. Jahangir Alam ChowdhuryUniversity of Dhaka

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Business Research Methodology

Chapter 02

Chapter 02

The Research Process: Coming to TermsThe Research Process: Coming to Terms


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Chapter 02

From Problem to Solution All you need to do is to identify an interesting question,

collect some some data, and proof!-instant research! Not quite. The model of scientific inquiry does a nice job of specifying the steps in the research process, but there is quite a bit more to the process than that.

Duckett and Richards (1989). “Maternal Employment and Young Adolescents’ Daily Experience in

Single-Mother Families”. The objective of the study is to examine the impact of maternal

employment on adolescent development. Sample: 436 fifth through ninth graders and their mothers. The researchers compared adolescents living with two parents (88%)

with adolescents living with only their mother. A signal telling the participant to stop and complete the form was

sent on an average of every two hours between 7:30 AM and 9:30 PM, with a total of 49 signals sent for the week for each participant (in total 21, 364 forms).


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Chapter 02

The Language of Research Many different terms are used in the research community, and

the faster you become familiar with them, the easier the entire process will be to understand.

All About Variables The word variable has several synonyms, such as

changeable or unsteady. Our set of rules tells us that a variable is a noun, not an adjective, and represents a class of out-comes that can take on more than one value.

For example height (expressed as short or tall, or 5 feet, 3 inches or 6 feet, 1 inch), weight (expressed as heavy or light, 128 pounds or 150 pounds), age at immunization (expressed as young or old, 6 weeks or 18 months), number of words remembered, time off work, political party affiliation,


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Chapter 02

Types of Variables

T y p e o f V a ria b le

D efin itio n ,

O th er T erm s Y o u M ig h t S e e

Dependent A variable that is measured to see whether the treatment or manipulation of the independent variable had an effect

• Outcome variable • Results variable • Criterion variable

Independent A variable that is manipulated to examine its impact on a dependent variable

• Treatment variable • Factor • Predictor variable

Control A variable that is related to the dependent variable. the influence of which needs to be removed

• Restricting variable

Extraneous A variable that is related to the dependent variable or independent variable that is not part of the experiment

• Threatening variable

Moderator A variable that is related to the dependent variable or independent variable and has an impact on the dependent variable

• Interacting variable


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Chapter 02

Types of Variables A dependent variable represents the measure that reflects the

outcomes of a research study. For example, if you measure the difference between two groups of

adults on how well they can remember a set of ten single digits after a five-hour period, the number of digits remembered is the dependent variable. Another example: If you are looking at the effect of parental involvement in school on children's grades, the grades that the children received would be considered a dependent variable.

An independent variable represents the treatments or conditions that the researcher has either direct or indirect control over to test their effects on a particular outcome.

Independent variable is also known as a treatment variable. For example, age and education of the respondent.


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Chapter 02

Types of Variables A control variable is a variable that has a potential influence on the

dependent variable; consequently, the influence must be removed or controlled.

For example, if you are interested in examining the relationship between reading speed and reading comprehension, you may want to control for differences in intelligence. Because intelligence is related both to reading speed and to reading comprehension. Intelligence must be held constant for you to get a good idea of the nature of the relationship between the variables of interest.

An extraneous variable is a variable that has an unpredictable impact upon the dependent variable.

For example, if you are interested in examining the effects of television watching on achievement, you might find that the type of television programs watched is an extraneous variable that might affect achievement. Such programs as Discovery, Nova, Sesame Street, and 3-2-1 Contact might have a positive impact on achievement, whereas other programs might have a negative impact.


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Chapter 02

Types of Variables A moderator variable is a variable that is related to the variables

of interest (such as the dependent and independent variable), masking the true relationship between the independent and dependent variable.

For example, if you are examining the relationship between crime rate and ice cream consumption, you need to include temperature because it moderates that relationship.


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Chapter 02

Hypothesis A hypothesis was defined as "an educated guess."

Although a hypothesis reflects many other things, perhaps its most important role is to reflect the general problem statement or the question that was the motivation for undertaking the research study.

That is why taking care' and time with that initial question is so important. Such consideration can guide you through the creation of a hypothesis, which in turn helps you to determine the types of techniques you will use to test the hypothesis and answer the original question.

The "I wonder ... " stage becomes the problem statement stage, which then leads to the study's hypothesis. Here is an example of each of these.


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Chapter 02

Hypothesis “I wonder"

It seems to me that several things could be done to help our employees-lower their high absentee rate. Talking with some of them tells me that they are concerned about after-school care for their children. I wonder what would happen if a program were started right here in the factory to provide child supervision and activities?

The hypothesis: Parents who enroll their children in after-school programs will miss

fewer days of work in one year and will have a more positive attitude toward work as measured by the Attitude Toward Work (ATW) survey than parents who do not enroll their children in such programs.

A good hypothesis provides a transition from a problem statement into a form that is more amenable to testing using the research methods.


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Chapter 02

Null Hypothesis A null hypothesis is an interesting little creature. If it could talk, it

would say something like, "I represent no relationship between the variables that you are studying."

In other words, null hypotheses are statements of equality such as, There will be no difference in the average score of ninth graders and

the average score of twelfth graders on the ABC memory test. A null hypothesis, such as the ones described here, would be

represented by the following equation:

Two purposes of null hypothesis: First, the null hypothesis acts as a starting point because it is the state

of affairs that is accepted as true in the absence of other information. The second purpose of the null hypothesis is to provide a benchmark

against which observed outcomes can be compared to determine whether these differences are caused by chance or by some other factor.


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Chapter 02

Hypothesis The Research Hypothesis

Whereas a null hypothesis is a statement of no relationship between variables, a research hypothesis is a definite statement of the relationship between two variables.

For example, for each of the null hypotheses stated earlier, there is a corresponding research hypothesis.

there can certainly be more than one research hypothesis for anyone null hypothesis.

For example:

The average score of ninth graders is different from the average score of twelfth graders on the ABC memory test.

There is a relationship between personality type and job success.


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Chapter 02

Hypothesis The Non-directional Research Hypothesis

A non-directional research hypothesis reflects a difference between groups, but the direction of the difference is not specified.

For example, the research hypothesis The average score of ninth graders is different from the average score of twelfth graders on the ABC memory test is non-directional in that the direction of the difference between the two groups is not specified.

The hypothesis states only that there is a difference and says nothing about the direction of that difference. It is a research hypothesis because a difference is hypothesized, but the nature of the difference is not specified.

A non-directional research hypothesis such as the one described here would be represented by the following equation:


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Chapter 02

Hypothesis The Directional Research Hypothesis

A directional research hypothesis reflects a difference between groups, and the direction of the difference is specified.

For example, the research hypothesis The average score of twelfth graders is greater than the average score of ninth graders on the ABC memory test is directional, because the direction of the difference between the two groups is specified-one group's score is hypothesized to be greater than the other.

Directional hypotheses can take the following forms:

A is greater than B (or A> B) B is greater than A (or B > A)

It can be represented by the following equation:


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Chapter 02

Null Hypothesis Vs. Research Hypothesis The null hypothesis represents an equality and the research hypothesis

represents an inequality. There are several important differences between these two types of

hypotheses. First, the null hypothesis states that there is no relationship between

variables (an equality), whereas the research hypothesis states that there is a relationship (an inequality).

Second, null hypotheses always refer to the population, whereas research hypotheses always refer to the sample.

Third, because the entire population cannot be directly tested (again, it is impractical, uneconomical, and often impossible), you can never really say that there is actually no difference between groups (or an inequality) on a specified dependent variable (if you accept the null hypothesis). Rather, you have to infer it (indirectly) from the results of the test of the research hypothesis, which is based on the sample.

Hence, the null hypothesis must be indirectly tested, whereas the research hypothesis is directly tested.


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Chapter 02

What Makes a “Good” Hypothesis?

The criteria we want to apply to a "good" hypothesis:

A good hypothesis is stated in declarative form, not as a question. Hypotheses are most effective when they make a clear and forceful statement.

A good hypothesis posits an expected relationship between variables.

Hypotheses reflect the theory or literature upon which they are based.

A hypothesis should be brief and to the point.

Good hypotheses are testable hypotheses.


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Chapter 02

Samples and Populations Given the constraints of limited time and limited research funds, the

best strategy is to take a portion of a larger group of participants and do the research with that smaller group.

The larger group is referred to as a population, and The smaller group selected from a population is referred to as a

sample. Samples should be selected from populations in such a way that you

maximize the likelihood that the sample represents the population as much as possible.

The goal is to have the sample resemble the population as much as possible.

The most important implication of ensuring similarity between the two is that, once the research is finished, the results based on the sample can be generalized to the population.

When the sample does represent the population, the results of the study are said to be generalizable or to have generalizability.


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Chapter 02

The Concept of Significance

Significance is a measure of how much risk we are willing to take when reaching a conclusion about the relationship between variables.

Let's modify the meaning of "differences " to include the adjective "significant." Here, significant differences are the differences observed between adolescents of mothers who work and of those who do not that are due to some influence and do not appear just by chance.

Because the world and you and I and the research process are not perfect, one must allow for some leeway. In other words, you need to be able to say that, although you are pretty sure the difference between the two groups of adolescents is due to the mothers‘ working, you cannot be absolutely, 100%, positively, unequivocally, indisputably sure.


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Chapter 02

The Concept of Significance

In most scientific endeavors that involve proposing hypotheses and examining differences between groups, there is bound to be a certain amount of error that simply cannot be controlled.

Significance level is the risk associated with not being 100% confident that the difference is caused by what you think and may be due to some unforeseen factor.

Significant findings at the .05 level (p < .05), the translation is that a chance of less than 1 in 20 (or .05 or 5%) exists that any differences found between the groups were not due to the hypothesized reason (the independent variable in the case of a comparison between two groups) but to some other unknown reason or reasons.


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Chapter 02

Thank You

Chap02

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